Standby was not starting.
Standby Alert log shows
destination database instance is 'started' not 'mounted'
Standby was not starting.
only starts till nomount.
alter database mount causes the following in alert log
destination database instance is 'started' not 'mounted'
on standby db_file_recovery_dest_size value was very low than primary.
after setting db_file_Recovery_dest_size eqaul to primary standby database started.
could any one throw some light how this could have solved the issue.